docs: def anat_info(suffix, metadata, img, config):
      """
      Generate a paragraph describing T1- and T2-weighted structural scans.
  
      Parameters
      ----------
      suffix : :obj:`str`
          T1 or T2.
      metadata : :obj:`dict`
          Data from the json file associated with the scan, in dictionary
          form.
      img : :obj:`nibabel.Nifti1Image`
          The nifti image of the scan.
      config : :obj:`dict`
          A dictionary with relevant information regarding sequences, sequence
          variants, phase encoding directions, and task names.
  
      Returns
      -------
      desc : :obj:`str`
          A description of the scan's acquisition information.
      """
      n_slices, vs_str, ms_str, fov_str = get_sizestr(img)
      seqs, variants = get_seqstr(config, metadata)
  
      if 'EchoTime' in metadata.keys():
          te = num_to_str(metadata['EchoTime']*1000)
      else:
          te = 'UNKNOWN'
  
      desc = '''
             {suffix} {variants} {seqs} structural MRI data were collected
             ({n_slices} slices; repetition time, TR={tr}ms;
             echo time, TE={te}ms; flip angle, FA={fa}<deg>;
             field of view, FOV={fov}mm; matrix size={ms}; voxel size={vs}mm).
             '''.format(suffix=suffix,
                        variants=variants,
                        seqs=seqs,
                        n_slices=n_slices,
                        tr=num_to_str(metadata['RepetitionTime']*1000),
                        te=te,
                        fa=metadata.get('FlipAngle', 'UNKNOWN'),
                        vs=vs_str,
                        fov=fov_str,
                        ms=ms_str,
                       )
      desc = desc.replace('\n', ' ').lstrip()
      while '  ' in desc:
          desc = desc.replace('  ', ' ')
  
      return desc